---
slug: 30-agent-memory-state
role: index
date: 2026-04-21
---

> **📅 Research snapshot as of 2026-04-21.** Provider pricing, free-tier availability, and model capabilities drift every quarter. The router reads `data/routing-table.json` and `data/model-registry.json` at runtime — treat those as source of truth. If this document disagrees with the registry, the registry wins.

# Category 30 — Agent Memory State

Agent memory architectures (Letta, Zep, mem0), session vs long-term memory, MCP resources as persistent state, user-preference learning, asset-set coherence tracking.

## Angles

| File | Topic |
|---|---|
| [`30a-agent-memory-architectures.md`](./30a-agent-memory-architectures.md) | Agent Memory Architectures |
| [`30b-session-vs-longterm-memory.md`](./30b-session-vs-longterm-memory.md) | Session vs Long-Term Memory |
| [`30c-mcp-resources-persistent-state.md`](./30c-mcp-resources-persistent-state.md) | MCP Resources and Persistent State |
| [`30d-user-preference-learning.md`](./30d-user-preference-learning.md) | User Preference Learning |
| [`30e-asset-set-coherence-tracking.md`](./30e-asset-set-coherence-tracking.md) | Asset Set Coherence Tracking |

## Also in this folder

- [`SYNTHESIS.md`](./SYNTHESIS.md) — synthesized insights across angles

## Up one level

- [`../index.md`](../index.md) — master research index
- [`../SYNTHESIS.md`](../SYNTHESIS.md) — master synthesis
